public class demo3 {
    public int uniquePaths(int m, int n) {
        int [][]arr=new int[m+1][n+1];
        arr[0][1]=1;
        for(int i=1;i<=m;i++){
            for(int j=1;j<=n;j++){
                arr[i][j]=arr[i-1][j]+arr[i][j-1];
            }
        }
        return arr[m][n];
    }
}
